If you have air bubbles comming from the fuel tank to the engine you have a problem. Did you wrap the tank in foam rubber? Vibration will cause fuel foaming and this will lean your engine out but will not cause the starting issues your having. (cause the fuel hasn't foamed yet) Are you using a starter or flipping it over by hand? Does it say in the manual that for break the high speed needle should be set to 1 and 1/8th? That sounds more of a setting for after the engine is broken in, and for break in 2 to 2 1/2 should at least get you in the ballpark. Since it's a ringed engine you want to break it in slobbering rich the first couple runs. It needs to be full throttle controlling engine speed with the high speed needle. What exactly does the break in proceedure in the manual say to do? Check your fuel lines and padding on the fuel tank first to figure out why your getting air bubbles comming from the tank. Then let us know what the manual states for a break in proceedure to check your high speed needle settings.